The objective of this study was to investigate the affect of camera height as a function of volume width on lower limb kinematics during normal walking using Theia3D. Video data was recorded for 9 subjects using 32 Sony RX0II cameras and processed in Theia3D (v2023.1.0.3161p9, model v10.0.0, 3DOF knee, 8 Hz cutoff frequency).
Camera Heights and Volume widths
Camera Heights
The 32 cameras were placed in a standard ellipse-like configuration (see
Figure 1). Cameras were placed at 4 heights for each
camera location:
Group 0 included all 32 cameras during processing.
Volume Width
For each width the cameras were moved and re-aimed to get the subject in
all camera views as much as possible given the width constraints.
Width 1 was the standard HMRL volume length (~13.8m Long) and width. Width 2 and 3 were narrower. With width 3 trying to simulate hallway.
A 5th and 6th group were added to Width 3 since the sagittal cameras for groups 1 and 2 could not get the full subjects. The sagittal cameras were replaced with videos from group 3.
Calibration
A single calibration was performed for each width with all 32 cameras.
Separate calibration files were then built by extracting the cameras for
each group
Data Processing
Only steps within a regional of interest were kept for analysis. The
region was defined to only include steps where the subject was visible
by all cameras. The same region was applied to each grouping to ensure
the same steps were used for analysis. The number of steps included
reduced as a function of width.
Data only shown for Right Leg.
The plots are interactive:
Draft interpretations per Jereme and Rob: